Mention Result<!, E> in never docs. #49988

clarfonthey · 2018-04-15T21:07:37Z

rust-highfive · 2018-04-15T21:07:47Z

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sfackler · 2018-04-15T21:09:05Z

rust-highfive · 2018-04-15T21:21:12Z

Your PR failed on Travis (raw log). Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

Click to expand the log.

[00:00:46] configure: rust.quiet-tests     := True
---
[00:05:40] tidy error: /checkout/src/libstd/primitive_docs.rs:178: trailing whitespace
[00:05:41] some tidy checks failed
[00:05:41]
[00:05:41]
[00:05:41] command did not execute successfully: "/checkout/obj/build/x86_64-unknown-linux-gnu/stage0-tools-bin/tidy" "/checkout/src" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage0/bin/cargo" "--no-vendor" "--quiet"
[00:05:41] expected success, got: exit code: 1
[00:05:41]
[00:05:41]
[00:05:41] failed to run: /checkout/obj/build/bootstrap/debug/bootstrap test src/tools/tidy
[00:05:41] Build completed unsuccessfully in 0:02:32
[00:05:41] make: *** [tidy] Error 1
[00:05:41] Makefile:79: recipe for target 'tidy' failed
---
$ ls -lat $HOME/Library/Logs/DiagnosticReports/
ls: cannot access /home/travis/Library/Logs/DiagnosticReports/: No such file or directory
travis_time:end:15693899:start=1523827160198752133,finish=1523827160206541759,duration=7789626
travis_fold:end:after_failure.2
travis_fold:start:after_failure.3
travis_time:start:0240e069
$ find $HOME/Library/Logs/DiagnosticReports -type f -name '*.crash' -not -name '*.stage2-*.crash' -not -name 'com.apple.CoreSimulator.CoreSimulatorService-*.crash' -exec printf travis_fold":start:crashlog\n\033[31;1m%s\033[0m\n" {} \; -exec head -750 {} \; -exec echo travis_fold":"end:crashlog \; || true
find: `/home/travis/Library/Logs/DiagnosticReports': No such file or directory
travis_time:end:0240e069:start=1523827160213176373,finish=1523827160220525100,duration=7348727
travis_fold:end:after_failure.3
travis_fold:start:after_failure.4
travis_time:start:35dadb14
$ dmesg | grep -i kill
[   10.523986] init: failsafe main process (1095) killed by TERM signal

I'm a bot! I can only do what humans tell me to, so if this was not helpful or you have suggestions for improvements, please ping or otherwise contact @TimNN. (Feature Requests)

rust-highfive · 2018-04-15T21:52:35Z

Your PR failed on Travis (raw log). Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

Click to expand the log.

[00:00:47] configure: rust.quiet-tests     := True
---
[00:05:14] tidy error: /checkout/src/libstd/primitive_docs.rs:178: trailing whitespace
[00:05:15] some tidy checks failed
[00:05:15]
[00:05:15]
[00:05:15] command did not execute successfully: "/checkout/obj/build/x86_64-unknown-linux-gnu/stage0-tools-bin/tidy" "/checkout/src" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage0/bin/cargo" "--no-vendor" "--quiet"
[00:05:15] expected success, got: exit code: 1
[00:05:15]
[00:05:15]
[00:05:15] failed to run: /checkout/obj/build/bootstrap/debug/bootstrap test src/tools/tidy
[00:05:15] Build completed unsuccessfully in 0:02:02
[00:05:15] make: *** [tidy] Error 1
[00:05:15] Makefile:79: recipe for target 'tidy' failed
---
$ ls -lat $HOME/Library/Logs/DiagnosticReports/
ls: cannot access /home/travis/Library/Logs/DiagnosticReports/: No such file or directory
travis_time:end:2bb44d5a:start=1523828998949416604,finish=1523828998956771530,duration=7354926
travis_fold:end:after_failure.2
travis_fold:start:after_failure.3
travis_time:start:056baa30
$ find $HOME/Library/Logs/DiagnosticReports -type f -name '*.crash' -not -name '*.stage2-*.crash' -not -name 'com.apple.CoreSimulator.CoreSimulatorService-*.crash' -exec printf travis_fold":start:crashlog\n\033[31;1m%s\033[0m\n" {} \; -exec head -750 {} \; -exec echo travis_fold":"end:crashlog \; || true
find: `/home/travis/Library/Logs/DiagnosticReports': No such file or directory
travis_time:end:056baa30:start=1523828998962745853,finish=1523828998969647555,duration=6901702
travis_fold:end:after_failure.3
travis_fold:start:after_failure.4
travis_time:start:060dfafd
$ dmesg | grep -i kill
[   10.817069] init: failsafe main process (1092) killed by TERM signal

I'm a bot! I can only do what humans tell me to, so if this was not helpful or you have suggestions for improvements, please ping or otherwise contact @TimNN. (Feature Requests)

rust-highfive · 2018-04-15T22:40:38Z

Your PR failed on Travis (raw log). Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

Click to expand the log.

[00:00:46] configure: rust.quiet-tests     := True
---
[00:48:39] .................................................................................i..................
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[00:56:13] ....................................................................................................
[00:56:39] .......i............................................................................................
[00:57:06] ...i............................................................................test [run-pass] run-pass/mir_heavy_promoted.rs has been running for over 60 seconds
[00:57:16] ....................
[00:57:49] ....................................................................................................
[00:58:22] .....................................................................ii.............................
[00:59:13] ................................i...........................................test [run-pass] run-pass/saturating-float-casts.rs has been running for over 60 seconds
[00:59:21] .........i.ii...........
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---
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[01:06:53] iiii.......i..i........i..i.i.............i..........iiii...........i...i..........ii.i.i.......ii..
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[01:31:32] .....iiii...............................................
[01:31:32] failures:
[01:31:32]
[01:31:32] ---- primitive_docs.rs - prim_never (line 154) stdout ----
[01:31:32]  error[E0425]: cannot find function `get_request` in this scope
[01:31:32]  --> primitive_docs.rs:156:29
[01:31:32]   |
[01:31:32] 5 |     let (client, request) = get_request().expect("disconnected");
[01:31:32]   |                             ^^^^^^^^^^^ not found in this scope
[01:31:32]
[01:31:32] thread 'primitive_docs.rs - prim_never (line 154)' panicked at 'couldn't compile the test', librustdoc/test.rs:318:13
[01:31:32] note: Run with `RUST_BACKTRACE=1` for a backtrace.
[01:31:32]
[01:31:32] ---- primitive_docs.rs - prim_never (line 167) stdout ----
[01:31:32]  error[E0425]: cannot find function `get_request` in this scope
[01:31:32]  --> primitive_docs.rs:169:11
[01:31:32]   |
[01:31:32] 5 |     match get_request() {
[01:31:32]   |           ^^^^^^^^^^^ not found in this scope
[01:31:32]
[01:31:32] thread 'primitive_docs.rs - prim_never (line 167)' panicked at 'couldn't compile the test', librustdoc/test.rs:318:13
[01:31:32]
[01:31:32] ---- primitive_docs.rs - prim_never (line 182) stdout ----
[01:31:32]  error[E0412]: cannot find type `ConnectionError` in this scope
[01:31:32]  --> primitive_docs.rs:183:31
[01:31:32]   |
[01:31:32] 4 | fn server_loop() -> Result<!, ConnectionError> {
[01:31:32]   |                               ^^^^^^^^^^^^^^^ not found in this scope
[01:31:32]
[01:31:32] error[E0425]: cannot find function `get_request` in this scope
[01:31:32]  --> primitive_docs.rs:185:33
[01:31:32]   |
[01:31:32] 6 |         let (client, request) = get_request()?;
[01:31:32]   |                                 ^^^^^^^^^^^ not found in this scope
[01:31:32]
[01:31:32] error: unreachable expression
[01:31:32]  --> primitive_docs.rs:184:5
[01:31:32]   |
[01:31:32] 5 | /     Ok(loop {
[01:31:32] 6 | |         let (client, request) = get_request()?;
[01:31:32] 7 | |         let response = request.process();
[01:31:32] 8 | |         response.send(client);
[01:31:32] 9 | |     })
[01:31:32]   | |______^
---
[01:31:32]   = note: #[deny(unreachable_code)] implied by #[deny(warnings)]
[01:31:32]
[01:31:32] thread 'primitive_docs.rs - prim_never (line 182)' panicked at 'couldn't compile the test', librustdoc/test.rs:318:13
---
[01:31:32] command did not execute successfully: "/checkout/obj/build/x86_64-unknown-linux-gnu/stage0/bin/cargo" "test" "--target" "x86_64-unknown-linux-gnu" "--release" "--locked" "--color" "always" "--features" "panic-unwind jemalloc backtrace" "--manifest-path" "/checkout/src/libstd/Cargo.toml" "-p" "std" "--" "--quiet"
[01:31:32] expected success, got: exit code: 101
[01:31:32]
[01:31:32]
[01:31:32] failed to run: /checkout/obj/build/bootstrap/debug/bootstrap test
[01:31:32] Build completed unsuccessfully in 0:44:15
[01:31:32] Makefile:58: recipe for target 'check' failed
[01:31:32] make: *** [check] Error 1
---
121760 ./obj/build/bootstrap/debug/incremental/bootstrap-351vorei3hhuv/s-f05gazxpuo-1560aao-3ssff2uugm5rt
---
102512 ./obj/build/x86_64-unknown-linux-gnu/stage1-std/x86_64-unknown-linux-gnu/release/incremental/core-31lccp6wy7orz/s-f05hha4jpu-3sh9uk-bcs1sclq83s
100744 ./obj/build/bootstrap/debug/incremental/bootstrap-zki88qpb4pjm
100740 ./obj/build/bootstrap/debug/incremental/bootstrap-zki88qpb4pjm/s-f05hk45zgm-1798b1g-2fm8hlvdg42qh
---
55760 ./obj/build/x86_64-unknown-linux-gnu/stage1-rustc/x86_64-unknown-linux-gnu/release/incremental/syntax-33oa6nnkk1g08/s-f05hj8jf9t-xeq3dt-1h8qobzzqy5ls

I'm a bot! I can only do what humans tell me to, so if this was not helpful or you have suggestions for improvements, please ping or otherwise contact @TimNN. (Feature Requests)

bluetech · 2018-04-16T16:37:20Z

src/libstd/primitive_docs.rs

@@ -112,6 +112,8 @@ mod prim_bool { }
 ///
 /// # `!` and generics
 ///
+/// ## Infalliable errors


Typo: Infalliable -> Infallible

this still needs fixed

bluetech · 2018-04-16T16:37:46Z

src/libstd/primitive_docs.rs

@@ -140,9 +142,59 @@ mod prim_bool { }
 /// [`Ok`] variant. This illustrates another behaviour of `!` - it can be used to "delete" certain
 /// enum variants from generic types like `Result`.
 ///
+/// ## Infinite loops
+///
+/// While [`Result<T, !>`] is very useful for removing errors, `!` can also be used to removed


Typo: removed -> remove

scottmcm · 2018-04-17T08:30:38Z

src/libstd/primitive_docs.rs

+/// instead:
+///
+/// ```ignore (hypothetical-example)
+/// fn server_loop() -> Result<!, ConnectionError> {


I really like this example 👍 A thought: with #49162, it could even be

fn main() -> Result<!, ConnectionError>

Also, I think the Ok( isn't needed because loop returns !, which will coerce to the Result: https://play.rust-lang.org/?gist=1cc0b7e8032bec565768ab95f42c454d&version=nightly

My main reasoning for not making this main is that the idea is that you might in principle want a larger loop that handles the error. Also, while I agree that the loop can be coerced to Ok, I think that wrapping in an Ok is best to draw parallels to a non-infinite loop. If it seems more clear the other way though, I'll definitely change it.

I'd prefer to leave off the Ok, but I can agree that this being not main makes a lot of sense

I'll leave off the Ok and explain the coercion.

pietroalbini · 2018-04-23T12:04:55Z

Ping from triage @steveklabnik! This PR needs your review!

steveklabnik

Some typos, but other than that, looks good! Thank you!

steveklabnik · 2018-04-23T13:41:00Z

src/libstd/primitive_docs.rs

@@ -112,6 +112,8 @@ mod prim_bool { }
 ///
 /// # `!` and generics
 ///
+/// ## Infalliable errors


this still needs fixed

steveklabnik · 2018-04-23T13:41:08Z

src/libstd/primitive_docs.rs

@@ -140,9 +142,59 @@ mod prim_bool { }
 /// [`Ok`] variant. This illustrates another behaviour of `!` - it can be used to "delete" certain
 /// enum variants from generic types like `Result`.
 ///
+/// ## Infinite loops
+///
+/// While [`Result<T, !>`] is very useful for removing errors, `!` can also be used to removed


steveklabnik · 2018-04-23T13:41:22Z

src/libstd/primitive_docs.rs

+///
+/// For example, consider the case of a simple web server, which can be simplified to:
+///
+/// ```ignore (hypothetical-example)


I've never seen this notation, does this work?

I actually copied it from an example earlier in the file, so, I assume so?

It doesn't do anything. It's recognized as non-rust code. That's pretty much all.

steveklabnik · 2018-04-23T13:42:09Z

src/libstd/primitive_docs.rs

+/// instead:
+///
+/// ```ignore (hypothetical-example)
+/// fn server_loop() -> Result<!, ConnectionError> {


I'd prefer to leave off the Ok, but I can agree that this being not main makes a lot of sense

clarfonthey · 2018-04-23T15:43:03Z

I'll try and make the desired changes later today.

aturon · 2018-04-25T01:59:21Z

@bors: rollup

clarfonthey · 2018-04-27T03:21:18Z

Err, I haven't made the changes yet.

clarfonthey · 2018-05-05T01:37:08Z

Actually made the changes; sorry it took so long.

rust-highfive · 2018-05-05T01:46:22Z

The job x86_64-gnu-llvm-3.9 of your PR failed on Travis (raw log). Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

Click to expand the log.


[00:04:56] travis_fold:start:tidy
travis_time:start:tidy
tidy check
[00:04:56] tidy error: /checkout/src/libstd/primitive_docs.rs:182: trailing whitespace
[00:04:57] some tidy checks failed
[00:04:57] 
[00:04:57] 
[00:04:57] command did not execute successfully: "/checkout/obj/build/x86_64-unknown-linux-gnu/stage0-tools-bin/tidy" "/checkout/src" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage0/bin/cargo" "--no-vendor" "--quiet"
[00:04:57] 
[00:04:57] 
[00:04:57] failed to run: /checkout/obj/build/bootstrap/debug/bootstrap test src/tools/tidy
[00:04:57] Build completed unsuccessfully in 0:02:01
[00:04:57] Build completed unsuccessfully in 0:02:01
[00:04:57] make: *** [tidy] Error 1
[00:04:57] Makefile:79: recipe for target 'tidy' failed

The command "stamp sh -x -c "$RUN_SCRIPT"" exited with 2.
travis_time:start:091df37c
$ date && (curl -fs --head https://google.com | grep ^Date: | sed 's/Date: //g' || true)

I'm a bot! I can only do what humans tell me to, so if this was not helpful or you have suggestions for improvements, please ping or otherwise contact @TimNN. (Feature Requests)

TimNN · 2018-05-08T17:26:09Z

Ping from triage @steveklabnik ! This PR is awaiting your review.

steveklabnik · 2018-05-08T19:29:04Z

@bors: r+ rollup

thanks!

bors · 2018-05-08T19:29:05Z

📌 Commit fc6d6c9 has been approved by steveklabnik

Mention Result<!, E> in never docs. Fixes rust-lang#48096.

Rollup of 11 pull requests Successful merges: - #49988 (Mention Result<!, E> in never docs.) - #50148 (turn `ManuallyDrop::new` into a constant function) - #50456 (Update the Cargo submodule) - #50460 (Make `String::new()` const) - #50464 (Remove some transmutes) - #50505 (Added regression function match value test) - #50511 (Add some explanations for #[must_use]) - #50525 (Optimize string handling in lit_token().) - #50527 (Cleanup a `use` in a raw_vec test) - #50539 (Add more logarithm constants) - #49523 (Update RELEASES.md for 1.26.0) Failed merges:

rust-highfive assigned sfackler Apr 15, 2018

rust-highfive added the S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. label Apr 15, 2018

rust-highfive assigned steveklabnik and unassigned sfackler Apr 15, 2018

clarfonthey force-pushed the never_docs branch from ca71dd0 to 360e64e Compare April 15, 2018 21:12

clarfonthey force-pushed the never_docs branch from 360e64e to 20a795e Compare April 15, 2018 21:43

Mention Result<!, E> in never docs.

20a795e

bluetech reviewed Apr 16, 2018

View reviewed changes

scottmcm reviewed Apr 17, 2018

View reviewed changes

steveklabnik suggested changes Apr 23, 2018

View reviewed changes

clarfonthey force-pushed the never_docs branch from 1a29882 to fc6d6c9 Compare May 5, 2018 04:17

Fixed typos

fc6d6c9

steveklabnik approved these changes May 8, 2018

View reviewed changes

bors added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels May 8, 2018

kennytm mentioned this pull request May 8, 2018

Rollup of 11 pull requests #50546

Merged

kennytm added a commit to kennytm/rust that referenced this pull request May 9, 2018

Rollup merge of rust-lang#49988 - clarcharr:never_docs, r=steveklabnik

bb690c6

Mention Result<!, E> in never docs. Fixes rust-lang#48096.

bors merged commit fc6d6c9 into rust-lang:master May 9, 2018

clarfonthey deleted the never_docs branch June 22, 2018 20:52

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Mention Result<!, E> in never docs. #49988

Mention Result<!, E> in never docs. #49988

clarfonthey commented Apr 15, 2018

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bors commented May 8, 2018

Mention Result<!, E> in never docs. #49988

Mention Result<!, E> in never docs. #49988

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clarfonthey commented Apr 15, 2018

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clarfonthey commented Apr 23, 2018

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clarfonthey commented May 5, 2018

rust-highfive commented May 5, 2018

TimNN commented May 8, 2018

steveklabnik commented May 8, 2018

bors commented May 8, 2018